Near-death experiences aren't figment of imagination, study shows

[American Patriot]

By Danielle Elliot /
CBS News/ August 12, 2013, 3:21 PM
Near-death experiences aren't figment of imagination, study shows



Nicolas Armer/AFP/Getty Images



The brain remains conscious after the heart stops beating, according to University of Michigan researchers. It may even function higher in the moments immediately following cardiac arrest than it does when the body is in a normal state.


The finding supports the shared experience of nearly 20 percent of people who have survived cardiac arrest. These survivors report having internal visions and heightened perception, known as near-death experiences, but the scientific reality of the experience has long been debated.


In a study published Monday in the Proceedings of the National Academy of Science, the team explains that in a study of nine rats, they observed continued brain activity even after the heart stopped beating and blood flow ceased. Compared to anesthesized and walking states, brain activity and coherence actually increased immediately following cardiac arrest. While the sample size is small, the results were observed in all nine of the rats studied.


"This study, performed in animals, is the first dealing with what happens to the neurophysiological state of the dying brain," lead study author Jimo Borjigin, Ph.D., associate professor of molecular and integrative physiology and associate professor of neurology at the University of Michigan Medical School, said in a statement.


"It will form the foundation for future human studies investigating mental experiences occurring in the dying brain, including seeing light during cardiac arrest," she added.

[American Patriot]

August 12, 2013

Media Contact: Shantell Kirkendoll 734-764-2220


Electrical signatures of consciousness in the dying brain

A University of Michigan animal study shows high electrical activity in the brain after clinical death


ANN ARBOR, Mich. -- The "near-death experience" reported by cardiac arrest survivors worldwide may be grounded in science, according to research at the University of Michigan Health System.
Mashour, Borjigin in lab.jpg

University of Michigan researchers George Mashour, M.D., Ph.D. and Jimo Borjigin, Ph.D., provide the first scientific framework for near-death experiences.





Whether and how the dying brain is capable of generating conscious activity has been vigorously debated.


But in this week’s PNAS Early Edition, a U-M study shows shortly after clinical death, in which the heart stops beating and blood stops flowing to the brain, rats display brain activity patterns characteristic of conscious perception.


“This study, performed in animals, is the first dealing with what happens to the neurophysiological state of the dying brain,” says lead study author Jimo Borjigin, Ph.D., associate professor of molecular and integrative physiology and associate professor of neurology at the University of Michigan Medical School.


“It will form the foundation for future human studies investigating mental experiences occurring in the dying brain, including seeing light during cardiac arrest,” she says.
Approximately 20 percent of cardiac arrest survivors report having had a near-death experience during clinical death. These visions and perceptions have been called “realer than real,” according to previous research, but it remains unclear whether the brain is capable of such activity after cardiac arrest.


“We reasoned that if near-death experience stems from brain activity, neural correlates of consciousness should be identifiable in humans or animals even after the cessation of cerebral blood flow,” she says.


Researchers analyzed the recordings of brain activity called electroencephalograms (EEGs) from nine anesthetized rats undergoing experimentally induced cardiac arrest.
Within the first 30 seconds after cardiac arrest, all of the rats displayed a widespread, transient surge of highly synchronized brain activity that had features associated with a highly aroused brain.


Furthermore, the authors observed nearly identical patterns in the dying brains of rats undergoing asphyxiation.


“The prediction that we would find some signs of conscious activity in the brain during cardiac arrest was confirmed with the data,” says Borjigin, who conceived the idea for the project in 2007 with study co-author neurologist Michael M. Wang, M.D., Ph.D., associate professor of neurology and associate professor of molecular and integrative physiology at the U-M.


“But, we were surprised by the high levels of activity,” adds study senior author anesthesiologist George Mashour, M.D., Ph.D., assistant professor of anesthesiology and neurosurgery at the U-M. “ In fact, at near-death, many known electrical signatures of consciousness exceeded levels found in the waking state, suggesting that the brain is capable of well-organized electrical activity during the early stage of clinical death.***”


The brain is assumed to be inactive during cardiac arrest. However the neurophysiological state of the brain immediately following cardiac arrest had not been systemically investigated until now.


The current study resulted from collaboration between the labs of Borjigin and Mashour, with U-M physicist UnCheol Lee, Ph.D., playing a critical role in analysis.
“This study tells us that reduction of oxygen or both oxygen and glucose during cardiac arrest can stimulate brain activity that is characteristic of conscious processing,” says Borjigin. “It also provides the first scientific framework for the near-death experiences reported by many cardiac arrest survivors.”

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Additional University of Michigan authors: Tiecheng Liu, Dinesh Pal, Sean Huff; Daniel Klarr, Jennifer Sloboda, and Jason Hernandez.
Reference: “Surge of Neurophysiological Coherence and Connectivity in the Dying Brain,” PNAS Early Edition, doi/10.1073/pnas.1308285110.
Funding: The work of George Mashour, M.D., Ph.D., was supported by National Institutes of Health Grant GM098578 and the James S. McDonnell Foundation.